If you want to request an autograph, follow the guidelines bellow. If you just want to mail a letter with the address above, and do not want anything back, then you can stop reading!
If you live in UK send a properly stamped and self addressed envelope (minimum size 8.5" x 4") with your request letter and a photo.
You can include a piece of cardboard to keep the photo from bending in shipping and also add "Do Not Bend" on the envelopes.
Send your letter and wait. On average, there is going to be a 3+ month wait for a response.
If you do not live in UK, you can purchase your British stamps here
*For information on postage prices to receive a letter from UK click here.

Feedback received:

Clive Anderson success - September 24th, 2013I sent a letter and SAE to Clive as well as 7 others in one envelope on: 29th July 2013, and yesterday I recieved this signed and personalized photo from him, plus letter thanking me for my letter.
address I used was:
United Agents LLP,
12-26, Lexington Street,
London
W1F OLE
Here is the pic:
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